For now, the default git remote is hard-coded as "origin". While this will work most of the time, having this being configurable would be nice.

Git handle this configuration separately for each branch so we can't reuse that system.

I guess the best way to do that would be using the git config system and having an entry like gitbug.defaultremote=origin.

In git-bug, we will also need a config package that read and expose this.